A variety of endeavors require determination of distance separation between objects. Such endeavors include aeronautics, emergency responders, surveying, biology field studies, and personnel management within large organizations. Range finding to a passive target that lacks a transceiver communicative with a system transceiver has historically been accomplished with triangulation or time of flight of an interrogating optical or radar pulse to the target and back to the system transceiver. These passive range finding systems are prone to distortions when line of sight conditions do not exist and are obscured by intermediate terrain and structures through which interrogating signals cannot penetrate. Additionally, radar systems are unable to provide high resolution distance separation information with an accuracy less than the radar wavelength scale.
Distance separation has also been previously determined using two communicative transceivers. With communicative active transceivers, distance separation is either calculated by absolute or relative techniques with absolute techniques utilizing distances or angles to known reference locations to calculate a target position. Exemplary of such absolute techniques are global positioning satellite (GPS) based systems, triangulation methods, and trilateration. In contrast, relative tracking involves a larger mobile unit that is tracked precisely in absolute coordinates using GPS or other tracking technologies while the actual target is then tracked with respect to the intermediate target. Regardless of the specifics, existing absolute and relative tracking techniques have all suffered from one or more of the following shortcomings including large transceiver size and power consumption, the requirement of clock synchronization that is vulnerable to air and disruption, limited penetration through land masses and/or manmade structures, or complexity of calculation. Attempts to add a distance separation tracking functionality onto existing communication devices that operate from 0.9-100 gigaHertz and in particular to industrial, scientific, and medical (ISM) 2.4 gigaHertz protocols have compounded these difficulties.
Thus, there exists a need for a distance separation tracking system that provides absolute positioning between system transceivers without reliance on external GPS interaction, gigaHertz wave propagation between system transceivers, or clock synchronization therebetween that have confounded prior art distance separation tracking processes. There further exists a need for a system that is amenable to being placed in a collar or otherwise carried by a human or other mammal or object desirous of being tracked.